An A-Z of Batteries – G, H and I

Written on May 13, 2016 at 3:21 pm

In this article,we continue our A-Z of all things battery (and get a little scientific along the way).

G is for Galvanic Cell

The key to how a car battery produces energy is down to a scientific invention known as the Galvanic Cell, named after prominent Italian scientist Luigi Aloisio Galvani. It is also sometimes referred to as the Voltaic Cell, after another Italian scientist – Allesandro Volta, who is widely credited as the inventor of the electric battery. Both scientists were fascinated by the concept of electricity – so much so that they frequently disagreed. Whilst they both made significant discoveries, it is probably more true to say that it was actually Volta who really invented the battery as we know it today.

Whilst most people refer to a single cell as a battery, by true definition a battery should always consist of multiple cells – just like in the automotive battery today.

In its simplest form, a Galvanic or Voltaic cell works on the principle that if contact is made between two different metals using a conductive material, energy is exchanged. The process is made more effective by submerging the two metals – known as the electrodes – in a highly conductive electrolyte solution. When electrode A has more negativity than electrode B, electrons are attracted to electrode B – creating a unidirectional electrical current.

Want to learn more? Click here to see a full description of the process on Wikipedia.

H is for Hydrometer

Have you ever had to diagnose automotive battery problems? Did you know that a battery hydrometer is actually widely considered to be the most effective way to determine whether a battery is fully charged?
So what is a battery hydrometer and how does it work? A hydrometer is an instrument that measures the specific gravity or relative density of a liquid. In English, that is the ratio of the density of the liquid to the density of water.

The state of charge of a lead-acid battery can be estimated from the density of the sulfuric acid solution used as electrolyte. A hydrometer calibrated to read specific gravity relative to water at 60 degrees Fahrenheit (15.5°C) is a standard tool for servicing automobile batteries. Tables are used to correct the reading to the standard temperature.

Random fact – the exact same principle can also be used to measure the quality of antifreeze solution.

I is for Ignition

Modern cars have more and more electronics, making battery reliability more important than ever. In addition, some cars also use a reserve battery as an additional power source for driving. The main purpose of a car battery, however, has not really changed for many years – to provide the power required to ignite the engine.

Whilst most automobiles require a single 12 volt battery for ignition, heavier industrial vehicles may need multiple batteries that are set up to provide a combined voltage of 24 volts.

There are two key measurements that reflect a battery’s suitability for a given vehicle – Ampere Hours (A-h) and Cold Cranking Amps (CCA). Amp hours refers to the amount of energy that can be stored by the battery and is a legal requirement in Europe. Cold Cranking Amps refers to the amount of current a battery can provide at 0 °C. Whilst this was an important consideration in older cars, modern fuel-injected cars tend to start within seconds, meaning that it is much less relevant today.

At Manbat, we are experts in automotive batteries. We supply and distribute top quality Varta, Lucas and Numax batteries across the entire UK. In addition, we are able to provide a wealth of resource for professionals in the automotive sector. To learn more or find your nearest distribution centre, contact us now.

Looking for a specific battery? Try the Manbat Battery Finder to get the best battery for any vehicle, along with technical specifications, fitting instructions, MSDS and more. Search instantly by registration mark, VIN or make/model.